To illustrate this: The senses do not perceive the law of gravitation, they only see its acts; but the power is there in all body, and is ever acting. So it is with our intuitions: we are not conscious of them as principles. We are conscious of their exercises, and argue that there must be internal laws which regulate them. Under this aspect they may be compared to seeds sending unseen roots downwards, and bearing branches and branchlets, leaves and fruit, upwards. They are often spoken of as latent, but ready to appear. The full truth was enunciated by Aristotle (De Anim. III. 4), Plato had spoken of the soul as νοητὸς τόπος, — the place of intelligence. Adopting this view, Aristotle calls the soul the depository of principles which are not in action, but in capacity, οὔτε ἐντελέχεια ἄλλα δυνάμει τὰ εἴδη. In this view they are in all men. It may be no easy work to enunciate them, but they are ruling in the mind. It has been found very difficult to state precisely the law of cause and effect, but all human beings, including children and savages, act upon it. So considered, our intuitions are properly characterized as first principles, fundamental laws of thought and belief, innate truths, a priori truths. III. They may take the form of Maxims or Axioms. So viewed, they are formed from our primitive perceptions, by a process of abstraction and generalization. We have the best examples of this in the axioms (kovai evvoiai) of Euclid, and in the commandments of the moral law, such as the Decalogue and the Sermon on the Mount. In this form they are not known by all men. Of the millions of people on the earth, including infants, children, savages, and the uneducated masses, there are comparatively few who fashion or employ such generalized principles. We do not need them to be so formulated in order to act upon them. Every human being, if he sees an object before him, say a house, will refuse his assent to the assertion that it does not exist; but how few beyond the limited circle of professed metaphysicians and logicians have consciously before them the principle that "it is impossible for the same thing to be and not to be at the same time!" Under this aspect they are properly designated as κοιναὶ ἔννοιαι, πρῶται ἔννοιαι, πρῶτα μοήματα, naturæ judicia, maxims and axioms. IV. These are only diverse aspects of the fundamental powers of human intelligence. They constitute a philosophic trinity, one in three and three in one. They appear first in consciousness as primary perceptions which look immediately on things. These imply principles which lead to the perceptions. The perceptions may be generalized and enunciated as laws. Till this is done they cannot be used in metaphysics considered as a science, or as philosophic principles. Under the second aspect they are in all men at all times, but they are not immediately perceived by the internal sense, and their nature cannot be made known to us except by careful observation of the acts, followed by abstraction and generalization. As generalized maxims they may be used as philosophic principles, but as such they are known only to a few, and they can be employed in discussion only when their law has been gathered by induction and properly expressed. While there should be no disputes as to the immediate convictions, there may be legitimate discussion as to whether they have been correctly generalized into axioms. In order to avoid confusion and the mistakes which proceed from confusion, it is essential that we go around these three sides of the shield, that we carefully distinguish them and read the inscription on each. Any one neglecting to do this will be liable to affirm of intuition. under one aspect what is true of it only under another, and to turn the wrong side towards the weapons of the assailant and keep the wrong side towards himself. It could be shown that many of the errors in metaphysics, both in its affirmations and denials, arise from looking at one or at only two of these aspects instead of looking at the whole. Most authors have not carefully noticed the difference between primitive perceptions which are singular and maxims which are universal. Locke looked upon them as ideas or perceptions in consciousness, and easily showed that they are not innate. The grand philosophic question discussed in the ages of Descartes, 1599-1650, and Locke, 1632-1704, was, Are there innate ideas? Descartes (and Herbert of Cherbury, 1581-1618) affirmed and Locke denied the existence of such ideas. The discussion was a confused one owing to the use of the word idea. Certain negative principles may be laid down. There are no innate ideas in the sense I. of images or phantasms, say of a good God or a good man; nor II. of an abstract or general notion, such as goodness or the good; nor III. of forms imposed on things by the mind, as was maintained by Kant. See the subject discussed in "Intuitions of the Mind," Part First, Book I. Chap. I. It is the aim of this treatise to show in what sense or senses there are intuitions in the mind. CHAPTER III. TESTS OF INTUITIVE TRUTHS. I. THE truths discovered at once by looking at things are called Intuitive. But how are we to know such truths, and distinguish them from other truths of observation or inference, or from propositions which are false? Are we entitled to appeal when we please, and as we please, to supposed infallible principles? Have we the privilege, when we are determined to adhere to a favorite opinion, to declare that we see it, that we feel it, to be true, and thus get rid of all objections, and even of the necessity of instituting an examination? When hard pressed in argument, may we fall back on an original conviction which we assume without evidence, and declare to be beyond the power of refutation? I believe we can furnish decisive tests of fundamental truths. II. Self-evidence is the Primary Mark of intuitive truth. It is evident on the bare inspection of the object. We perceive it to be so and so; we see it to be so at once without requiring any foreign evidence or mediate proof. That the planet Mars is inhabited, or that it is not, is not a first truth, is not a primitive truth, for it is not evident on the bare contemplation of the planet. That the isle of Madagascar is inhabited, though a truth, is not a primary truth; we believe it on secondary testimony. Nay, that the three angles of a triangle are together equal to two right angles is not seen to be true at once; it needs other truths coming between to prove it. But that there is an extended object before me when I look at a wall or a table; that I who look at the object exist; that two marbles added to two marbles here are equal in number to two marbles added to two marbles there, these are truths seen to be true on the bare contemplation of the things, and need no extraneous consideration to establish them. III. Necessity is a Secondary Mark. I must give my assent to the proposition, if I understand it. I cannot be made to believe the opposite. When a proposition is self-evident, necessity always attaches to our conviction regarding it. I am not inclined to fix on this as the original or essential characteristic. I shrink from maintaining that a proposition is true because it must be believed. A proposition is true as being true, and certain truths are seen by us to be self evidently true. I would not ground the evidence on the necessity of the belief: I would ascribe the irresistibility of the conviction to the self-evidence. IV. Catholicity, or universality of belief, is a Tertiary Test, that is, the conviction is entertained by all men when the objects are presented to the mind and apprehended. I am not disposed to use this, which has often been done, as the primary test. For in the first place it is not easy to determine in every case what propositions may claim the common consent of humanity. Even though this could be determined, it might be urged in the second place that this proves, not that the truth is |